Helicopter.



H. H. BERNHRD,

HEUCOPTER.

APPLlcAsoN FILED SEPT. 12. i911.

Patented Sept. 10, 1918.y

lllliilly v rm m NIIIIIIIIIIIHNIIIIIII UNITED STATES PATENT QFFICE..

HARRY H. BERNHARD, OF OAKLAND, CALIFORNIA. l il-;

HELICOPTER.

Specication of Letters Patent.

Patented Sept. 10, 1918.

Application filed September 12, 1917. Serial No. 191,077.

To all 'whom t may concern.'

Be it knowirthat I, HARRY H. BERNHARD, a citizen of the United States, residing at Oakland, in the county of Alameda and State of California, have invented new and useful Improvements in Helicopters, of which the following is a specification.

The present invention relates to improvements in helicopters, the object of the invention being to provide in a helicopter having upper and lower sets of blades revolving in opposite directions, means whereby a variation in the speed of either set of blades Will be automatically communicated to the other set, so that at all times the blades will neutralize each other as totheir turning elfect on the machine.

In the accompanying drawing only such parts of the helicopter are shown as are necessary for the illustration of the invention, the remainder of the machine being omitted from the drawing. In said drawing, Figure 1 is a vertical section through the upper portion of the shaft of the helicopter; Fig. 2 is a horizontal section on the line 2-2 of Fig. 1; Fig. 3 is a view similar to Fig. 1 of a modified form of the invention. Referring to the drawing, 1 indicates a tubular frame from which the car and engine of the helicopter are suspended; 2 indicates a vertical shaft within said tubular frame and rotatable around its axis by a suitable engine connected thereto by a universal joint, both of these being omitted, as being common in the art.

To the upper portion of said shaft is secured, as by a pin 3, a spider 4;, having radiating arms 5, on cylindrical portions of which are mounted gear wheels 6, which mesh at their upper sides with a gear ring 7, formed on the under side of a disk 8, rotatable around the shaft 2 between said spider 4L and ball bearings 9, held in place by a collar 10 secured to said shaft. From said disk extend radiating upper blades 12.

At their lower sides said gear wheels 6 mesh with a gear ring 13, formed on the upper face of a ear wheel v14 rotatable around the shaft, which gear Wheel 14; meshes with pinions 16 rotatable around said stud shafts 17, screwed into a disk 18 secured to the tubular frame 1. Said pinions 16 mesh with an internal gear ring 19, formed on a hub 22, supported on ball bearings 23, on a collar 24E secured on the frame 1, and from said hub extend radially the lower set of blades 26.

It will be seen that with the above construction the upper and lower sets of blades rotate around the shaft 2 in opposite directions, and they are of such dimensions that any tendency of the machine to turn due to the oblique direction of one set of blades is neutralized by the other set of blades. Moreover, any variation in speed of either set of blades is immediately communicated to the other set, so that they are at all times equally balanced.

In the modification of the invention, shown in Fig. 3, instead of the pinions 16, there are employed pinions 27 which mesh with an internal gear ring 28 on a wheel 29 rotated like the gear ring 13, which pinions 27 are mounted on vertical shafts 30 extending through a wheel 31 attached to the frame 1, to which shafts 31 are secured pinions 32 meshing with a gear ring 33 on a hub 34 on a Wheel 36 serving the same purpose as the hub 22 in the first form of the invention.

I claim: p

1. The combination of a rotary driving shaft, a stationary frame within which said shaft rotates, disks rotatable about the shaft, propeller blades secured to said disks, and means rotating with said shaft and operatively connected to both disks to rotate them in opposite directions.

2. The combination of a rotary driving shaft, a stationary frame within which said shaft rotates, a wheel turning with the shaft and having radially extending cylindrical portions, gear Wheels rotatably mounted on said cylindrical portions, a disk rotatable about the shaft and having a gear ring meshing with said gear wheels on one side, propeller blades secured to said disk, a ring rotatable about the shaft and having gear rings one of which meshes said gear wheels on the opposite side, shafts carried by said stationary frame, gear wheels secured to said shafts and meshing with the other of said latter gear rings, a disk rotatable about the frame and operatively connected to said last-named shafts to be rotated thereby, and blades connected to said last-named disk.

HARRY I-I. BERNHARD.

Copies of this patent may be obtained for ve cents each, by adressing the Commissioner of Patents',

Washington, D. G." 

